It would be nice to have some kind of indication what the text field on the datainput selection dialog is for, as it is not immediately obvious that it is a search bar. A tooltip at least, and perhaps a placeholder "Search..." text.

Also, it is possible to select an non-allowed type for a data input, which is odd. Maybe not use the term "allowed" for restricting the selection if they are all allowed. Check with UX.

Also, the currently selected data input should always be visible in the selection dialog, even if it doesn't match the selected filter, perhaps in a separate field.  Check with UX.